This invention relates to milk-based food products, and in particular to the microdispersal of vitamin E in milks (milkfat-based milk, skim milk, vegetable oil-filled milk, and blends thereof) at a level providing at least 31 IU (International Units) per serving. The invention also relates to a substantially lactose-free and milkfat-free composition for oral administration to a human or other mammal, including a microdispersed mixture of at least one mammalian milk protein or fragment thereof, and at least one fat-soluble micronutrient or pharmaceutical agent, where the weight ratio of said mammalian milk protein to said fat-soluble micronutrient or pharmaceutical agent is between 1:1 and 1000:1.
The information provided herein is solely to assist the understanding of the reader; none of that information or cited references is admitted to be prior art to the present invention.
In the past five years several major prospective health studies have been published demonstrating that vitamin E supplement ingestion is associated with a reduced risk of coronary heart disease (CHD) in both women and men (e.g., Stampfer et al., NEJM, 328, 1444-1449, 1993 Rimm et al., NEJM, 328, 1450-1456, 1993). In a four year study of nearly 40,000 males, Rimm et al., showed that the risk of CHD diminished significantly as the daily supplemental level of vitamin E increased. This study indicates that the current Recommended Daily Allowance (RDA) of 30 international units (IU) of vitamin E is insufficient for obtaining the full protective benefits of vitamin E. In fact, the study data suggest that for most adult males, a daily supplement of at least 100 IU of vitamin E is appropriate for helping to protect against CHD. In another prospective study, long-term ingestion of vitamin E was tested for its ability to reduce the incidence of myocardial infarction in patients having a documented condition of coronary atherosclerosis (Stephens et al., Lancet, 347, 781-786, 1996). In this study, it was shown that sustained supplementation of the patients"" diets with 400 IU of RRR-xcex1-tocopherol ingested once per day in capsules was sufficient to reduce the risk of non-fatal heart attacks by 77%. This protective effect became apparent after about 200 days of treatment with the vitamin. In still another study (Losonczy et al., Am. J. Clin. Nutr. 64, 190-196, 1996), individuals in an elderly population (n=11,178) aged 67-105, were each followed for 6 years, and their uses of vitamin E and/or vitamin C supplements were correlated with their risk of developing cancer and CHD. While vitamin C supplements could not be shown to have a significant protective effect over the 6 year period, vitamin E supplements (greater than 100 IU per day) were shown to reduce all-cause mortality 27-34%, CHD mortality 41-47%, and cancer mortality 22-23% (in these ranges, the first number is the age and sex-adjusted risk, and the second is a multi-covariable adjusted risk).
Many other studies have shown the beneficial function of vitamin E for protecting plasma LDL cholesterol and cellular components against oxidative damage, and for maintaining normal immunological function to protect the body against disease. It has also been shown in an 88 subject study, that even high daily doses of vitamin E ingested by healthy elderly people for extended periods of time (i.e., 800 IU per day for 4 months), caused no side-effects, no negative changes in general health or metabolic functions based upon an extensive battery of blood tests (Meydani et al., Am. J. Clin. Nutr. 68: 311-318, 1998). By contrast, significant improvements in T cell mediated function and significant increases in plasma vitamin E levels were noted. In that study, subjects consuming 800 IU of vitamin E per day for 4 months, reached plasma vitamin E levels of up to 71.5 xcexcmol per liter (3075 xcexcg per deciliter). This 3000 xcexcg per deciliter level is usually considered the xe2x80x9csaturation levelxe2x80x9d for vitamin E transport by lipoproteins in humans regularly consuming high doses of vitamin E, and is essentially 3.0xc3x97 the basal fasting plasma level of vitamin E (800-1000 xcexcg per deciliter) measured in the general population consuming no vitamin E dietary supplements.
As a result of a consensus in the scientific community on the benefits of supplemental vitamin E, a number of xe2x80x9cstructure-functionxe2x80x9d health claims for vitamin E have been approved under the Dietary Supplement Health and Education Act (DSHEA) in the United States. While the DSHEA does not encompass foods per se, in the last five years a number of food products supplemented or xe2x80x9cfortifiedxe2x80x9d with low levels of vitamin E have come to market. By the term xe2x80x9clow levelsxe2x80x9d it is meant that these foods provide quantities of vitamin E which are less than or equal to the current RDA of 30 IU of vitamin E per serving of the food. Typically, vitamin E is added to foods in one of its more chemically stable forms, e.g., xcex1-tocopherol acetate (also known as xcex1-tocopheryl acetate). Four different forms of vitamin E (the alcohol and ester forms of synthetic racemic (rac) vitamin E and the alcohol and ester forms of natural (RRR) vitamin E) are commercially available, and because of their differences in bioactivities and molecular weights, are assigned different values of specific activity (IU per milligram) according to the National Formulary as follows:
1 mg all-rac-xcex1-tocopherol acetate=1.00 IU
1 mg all-rac-xcex1-tocopherol=1.10 IU
1 mg RRR-xcex1-tocopherol acetate=1.36 IU
1 mg RRR- xcex1-tocopherol=1.49 IU
In a separate area of nutritional biochemistry, Perlman et al. in U.S. Pat. No. 5,514,407 combined vegetable oils rich in polyunsaturated fatty acids, with cholesterol-reduced animal fats rich in saturated fatty acids to produce oxidation-resistant fat blends containing 1-10 parts by weight of the animal fat to 1 part of vegetable oil. These blends showed favorable nutritional characteristics in mammals, including a decreased total serum cholesterol level, and a decreased LDL/HDL cholesterol ratio in humans. In Sundram et al., U.S. Pat. No. 5,578,334 and Sundram et al., U.S. Pat. No. 5,843,497 (which are hereby incorporated by reference in their entireties including drawings), certain vegetable oils such as soybean oil, rich in polyunsaturated fatty acids, were combined with palm oil, rich in saturated fatty acids, to produce dietary fat blends containing approximately equal proportions of saturated and polyunsaturated fatty acids (hereinafter termed xe2x80x9cbalanced fatsxe2x80x9d). Compared to diets in which one class of fatty acids predominates (polyunsaturated, monounsaturated or saturated), if such balanced fats are consumed as the principal dietary fat (at approximately 30% of dietary calories supplied as fat), the ratio of plasma LDL to HDL cholesterol is beneficially reduced. At the same time, HDL levels are beneficially sustained or increased.
Concerning the nutritional biochemistry of milk, many bioactive factors present in mammalian milks have been identified. These factors include anti-infectious and immunocompetent substances, and trophic factors (hormones, trophic peptides, nucleosides, nucleotides, polyamines). The digestion of some milk proteins including casein results in the release of certain biologically active peptides, also known as xe2x80x9cexorphinsxe2x80x9d, from within the larger protein sequences. For example, digestion of kappa-casein releases kappa-caseinoglycopeptide which is absorbed into the human bloodstream and beneficially inhibits platelet-fibrinogen binding and platelet aggregation (Chabance et al., Biochemie 80(2): 155-165, 1998). Other bioactive peptide fragments released from milk proteins have been reported. These include opioid receptor binding peptides, angiotensin converting enzyme inhibitory peptides, antimicrobial peptides, immunomodulating casein peptides that stimulate lymphocyte proliferation and macrophage activity, and beta- casein phosphopeptides. The latter are phosphorous-rich peptide fragments of casein, that inhibit precipitation of minerals by forming soluble complexes, improving gastrointestinal absorption of calcium and zinc (see review by Meisel, Biopolymers,43(2): 119-128, 1997; Hansen et al., J. Pediatr Gastroenterol Nutr., 24(1): 56-62, 1997; and Sato et al.,Biochim Biophys Acta, 1077(3): 413-415, 1991).
Concerning the uptake of vitamin E in mammals, several synthetic additives known for dispersing or dissolving fats and other lipophilic substances have been combined with vitamin E and reported to increase absorption of vitamin E. Greene et al., U.S. Pat. No. 5,179,122 describe a composition including vitamin E, an edible surfactant and an inert carrier for increasing the bioavailability of vitamin E. Julianto et al. (Int J Pharmaceutics, 200 (1): 53-57, 2000) describe a self-emulsifying formulation consisting of vitamin E dissolved in palm oil, plus a combination of the synthetic non-ionic surfactants, Tween 80 and Span 80 (esters and ester-ethers of fatty acids). DeMichele et al., U.S. Pat. No. 6,013,665 describe a method for enhancing absorption of a lipophilic compound such as an oil-soluble vitamin by administering structured triglycerides together with the lipophilic compound. In the Background section of U.S. Pat. No. 6,013,665, the authors also include a substantial review of the prior art describing xe2x80x9cabsorption promotersxe2x80x9d for lipophilic compounds such as vitamin E. These include combinations of vitamin E with medium chain and structured triglycerides for enteral and parenteral preparations, and vitamin E dispersed with lecithin and unsaturated fatty acids for dietary supplements. The patent also describes research in which the dietary inclusion of unsaturated fatty acids actually depresses vitamin E absorption. Likewise, ingestion of dietary fiber, e.g.,pectin, guar or cellulose, together with vitamin E and carotenoids has been reported to reduce the bioavailability of these antioxidants (Hoffmann et al., Eur J Nutr, 38(6): 278-285, 1999). In summary, research on food components and food additives which might stimulate the uptake or enhance the bioavailability of vitamin E has had limited success.
The present invention concerns the surprising discovery that absorption of vitamin E into the human bloodstream from milk is unexpectedly efficient compared with vitamin E absorption from other foods or from pharmaceutical preparations of vitamin E (e.g., capsules) and, therefore, further concerns the use of regular milk (with milkfat), skim milk (fat-free) and filled milk (milkfat being partially or fully substituted by vegetable oil) and other milk-based or milk-derived dairy products as carrier vehicles for microdispersed vitamin E. For example, the plasma level of vitamin E resulting from daily ingestion of 100 IU of vitamin E dispersed in milk is approximately equal to the plasma level of vitamin E which would result from daily ingestion of 300 IU per day in the form of a soft gel capsule. Furthermore, the enhanced plasma level of vitamin E resulting from ingesting vitamin E microdispersed in milk is surprisingly independent of the type of fat or even the amount of fat present in the milk. As a result of the highly efficient absorption of vitamin E from milk, milk provides a cost-effective means for supplementing vitamin E in the diet at a level sufficient to obtain the health benefits associated with high level vitamin E supplementation. In addition, providing vitamin E in milk at these beneficial levels provides a delivery mechanism which would be much better accepted by many individuals than taking vitamin pills daily. Applicant""s recent experimental data (see below) indicate that the component in milk promoting enhanced absorption of vitamin E is the protein portion of milk. In view of the abundance of casein in milk, casein""s ability to stabilize fat emulsions in milk, and the amphipathic character of this protein, it appears that casein stabilizes micelles containing vitamin E and/or other hydrophobic micronutrients and/or orally administered hydrophobic pharmacological agents, i.e., drugs, and promoting their absorption in the gut.
Thus, the invention involves the following interconnected discoveries:
(i) When vitamin E is microdispersed in milk, fat is not required in the milk product for hyper-efficient vitamin E absorption into the bloodstream. Thus, vitamin E dispersed in skim milk is as hyper-efficiently absorbed into the bloodstream as vitamin E dispersed in regular 1% milk.
(ii) The presence of a substantial proportion of polyunsaturated fats such as soybean oil, which generally inhibit vitamin E absorption, have been shown to produce no such inhibitory effect when co-dispersed with vitamin E in milk. Thus, non-hydrogenated polyunsaturated vegetable oil-containing filled milks can serve as efficient carriers for vitamin E supplements.
(iii) Ingestion of a vitamin E dose microdispersed in milk was found to be approximately 2-3 times more effective than the same dose ingested in capsule form for vitamin E doses exceeding approximately 50 IU per day. Thus, ingesting 100 IU of all-rac-xcex1-tocopherol acetate microdispersed in milk for 2-4 weeks demonstrated an equivalency of ingesting 300 IU of the same vitamin in the form of soft gel capsules in terms of elevating plasma and LDL levels of vitamin E.
(iv) Ingestion of a vitamin E dose of less than 50 IU per day microdispersed in milk, had a diminishing advantage over the same dose ingested in capsule form. In fact, with a dose of 30 IU vitamin E per day, it has been calculated that milk provides at most only a 38% greater increase (which is not a statistically significant increase) in the ratio of vitamin E/cholesterol than that which would achieved by ingesting one 30 IU vitamin E capsule.
(v) A dose of vitamin E microdispersed in orange juice was found to be much less efficiently absorbed and/or absorbed into lipoproteins than the same dose microdispersed in milk. In fact, with 200 IU of all-rac-xcex1-tocopherol acetate provided daily in orange juice, the increase in plasma vitamin E after 4 weeks was less than that achieved with 100 IU provided daily in milk.
(vi) Additionally, Applicants"" results from nutritional studies indicate that one or more milk proteins (or fragments produced via milk protein digestion) contribute to enhanced absorption and reduced excretion of vitamin E. These positive findings are consistent with our surprising negative findings that neither the presence nor the type of fat [see (i) and (ii) above], nor the presence of carbohydrate, e.g., lactose, contribute significantly to vitamin E uptake.
Regarding point (vi), it is mentioned in the Background that milk proteins, particularly the caseins, have been recognized for their ability to help stabilize emulsified milkfat in milk, e.g., homogenized milk. The amphipathic nature of beta-casein, including its phosphorylated amino terminal region, and the ability of regions of the beta-casein protein to undergo reversible random coil to alpha helix secondary structure transitions appear to be important in stabilizing fat emulsions. Furthermore, the peptide fragments of casein, e.g., its phosphopeptides (CPP), arising from digestive enzyme cleavage of casein have a number of other functions discussed above. For example, CPPs enhance the bioavailability/absorption of calcium and zinc. In the present invention, Applicants have discovered that milk proteins (particularly, casein and its digestion fragments) rather than milkfat, act to increase the absorption of fat-soluble micronutrients such as vitamin E.
In determining what components in fluid milk promote efficient absorption of microdispersed vitamin E, it is now evident that milk protein is largely responsible for this phenomenon. Preliminary experiments indicate that casein, which constitutes approximately 80% of the total protein in milk, is important in this absorption process. As casein is exposed to hydrolytic enzymes in the gastrointestinal tract and digested, protein fragments, i.e., peptides, such as phosphopeptides and glycopeptides are produced. These fragments as well as other milk proteins and/or their fragments, e.g., digestion fragments, may be important in the vitamin E absorption process as well as the intact casein molecule. Within the gastrointestinal tract, the sequence of events and molecular interplay between milk proteins, vitamin E, and the molecular transport system of the host (e.g., carrier proteins and receptor sites in the gastrointestinal tract) remain to be elucidated.
Accordingly, in one aspect, this invention features a composition for oral administration to humans and other mammals. The composition includes a mixture of at least one mammalian milk protein or fragment thereof, and at least one fat-soluble vitamin, in which the composition is substantially free of lactose and milkfat, and in which the weight ratio of the mammalian milk protein(s) or fragment(s) thereof, to the fat-soluble vitamin(s) is from 1:1 to 1000:1 inclusive, and the gastrointestinal absorption of the fat-soluble vitamin(s) is increased by ingesting this mixture rather than the fat-soluble vitamin alone.
Preferably the composition is not a liquid milk, (e.g., a whole, lowfat, nonfat, or filled milk), an evaporated milk, a condensed milk, or a powdered milk (as those terms are defined in the industry). Preferably the composition includes at least partially purified, or enriched, milk protein(s). Thus, the composition is preferably a xe2x80x9cnon-milkxe2x80x9d composition, meaning that it is not one of the milk products in this paragraph. Such xe2x80x9cnon-milkxe2x80x9d compositions or mixtures are also preferably applicable to the other related aspects herein.
The term xe2x80x9coral administrationxe2x80x9d is meant to include ingestion (of the composition) in foods, dietary supplements and pharmaceutical preparations.
The term xe2x80x9cfragmentxe2x80x9d is explained above, and is meant to include any portion of a larger protein. The protein fragment may include any or all side chains and derivatized amino acids, e.g., glycosylated and phosphorylated amino acids, carbohydrate side chains, and the like.
The term xe2x80x9cfat-soluble vitaminxe2x80x9d is meant to include any and all edible varieties of the vitamins A, D, E and K. Unlike typical milks and other dairy products which contain either or both lactose, i.e., milk sugar, and milkfat, the composition described herein is substantially free of both lactose and milkfat which are separated away from milk proteins during protein fractionation. The elimination or reduced presence of milkfat is desirable because natural milkfat contains cholesterol and, together with its myristic acid content, elevates the plasma cholesterol level in humans. Furthermore, milkfat would typically contribute unneeded energy calories. The elimination or reduced presence of lactose is desirable because lactose would also contribute unneeded energy calories, and because many people are lactose-intolerant, suffering intestinal upset with ingestion of lactose.
The term xe2x80x9csubstantially freexe2x80x9d indicates that at least two-thirds of the original level of each indicated substance has been removed, preferably at least 80%, 90%, 95%, 97%, 98%, 99% or even more.
The 1:1 to 1000:1 range for the weight ratio of milk protein to fat-soluble vitamin is intended to very broadly encompass the relative amount of protein present in a milk or other dairy product, and the amount of fat-soluble vitamin added to milk. Accordingly, in a 225 g serving of milk containing 4-5 g of casein protein and 50-100 IU (0.05-0.10g) of alpha-tocopheryl acetate, the ratio of protein to vitamin E is approximately 50:1 to 100:1. This ratio falls within the recited range of 1:1 to 1000:1. In particular embodiments the ratio is in the range 1:1 to 10:1, 10:1 to 50:1, 30:1 to 1000:1, 50.1 to 200:1, 100:1 to 300:1, 200:1 to 500:1, 400:1 to 700:1, or 600:1 to 1000:1.
In preferred embodiments of the above composition, the mammalian milk protein(s) is obtained, or the protein fragment(s) thereof is derived from bovine milk, i.e. cow""s milk. While cow""s milk is readily available in many countries, the milk proteins in other common mammalian milks including sheep and goat milk are expected to function in a similar manner to promote vitamin E absorption and are within the scope of the present invention.
In other preferred embodiments of this composition, at least one of the mammalian milk proteins or fragments thereof is a casein protein or protein fragment derived therefrom.
Preferably, within the casein group of proteins, the casein protein is selected from the group consisting of alpha casein, beta casein, kappa casein and protein fragments, glycopeptides and phosphopeptides derived from these caseins, and combinations thereof.
In other embodiments, at least one of the mammalian milk proteins or fragments thereof is a whey protein or protein fragment derived therefrom. Total casein and whey protein fractions are routinely obtained from milk, and these may be fractionated to yield single, i.e., individual casein whey proteins. These, as well as various enzymatic digestion products (protein fragments) derived therefrom are readily available from commercial sources and can be utilized.
In preferred embodiments, the whey protein is selected from the group consisting of lactoglobulin, lactalbumin, protein fragments derived therefrom, and combinations thereof.
In other preferred embodiments of the above composition, at least one fat-soluble vitamin is selected from the group consisting of vitamins A, D, E and K. Any edible and biologically active variety of these vitamins is suitable for use herein. The vitamins may be utilized singly or in any desired combination.
In a preferred embodiment, the at least one fat-soluble vitamin is vitamin E. The vitamin E is selected from the group consisting of alpha, beta, gamma and delta tocopherols, alpha, beta, gamma and delta tocotrienols, and combinations thereof.
Within the alpha tocopherol group, the vitamin E is selected from the group consisting of synthetic (all-rac) and natural (RRR) alpha-tocopherols, alpha-tocopheryl acetates, and alpha-tocopheryl succinates.
In another preferred embodiment of the above aspect, the mixture in the composition is a microdispersed blend of vitamin E and at least one mammalian milk protein or fragment thereof.
In other embodiments, the mixture is incorporated into a product selected from the group consisting of food products and dietary supplement products. The latter term is meant to include without limitation fat-soluble vitamin supplements, regardless of whether individual or multiple fat-soluble vitamins are included in the mixture, and regardless of whether the fat-soluble vitamin(s) are combined with any other ingredients such as water-soluble vitamins and other dietary supplements such as essential minerals (e.g.,calcium, potassium, magnesium, iron, zinc and selenium salts) amino acids, essential fatty acids and the like.
In other embodiments, the protein and vitamin mixture is selected from the group consisting of a mixture of solids, a mixture of liquids, and a combination thereof. In this context, the milk protein(s) and fat-soluble vitamins may be combined and co-emulsified as a xe2x80x9cmixture of liquidsxe2x80x9d such as that forming a stable emulsion containing vitamins microdispersed, e.g., homogenized, into an aqueous solution of milk protein, e.g., casein. If such an emulsion is rapidly dried, e.g., using a spray- or freeze-dry process, the resulting xe2x80x9cmixture of solidsxe2x80x9d contains the vitamin(s) and milk protein(s) microdispersed in one another.
In another embodiment, the vitamin and milk protein mixture is constituted as a microdispersed mixture as described above and previously defined. In this regard, the microdispersed mixture is a liquid mixture selected from the group including mixed emulsions, mixed suspensions, and combinations thereof that include at least one mammalian milk protein or fragment thereof and at least one fat-soluble vitamin.
In still another embodiment, the composition includes a mixture of at least one mammalian milk protein or fragment thereof and at least one fat soluble vitamin, in which the mixture has been dried from a liquid mixture selected from the group consisting of a mixed emulsion, a mixed suspension, and a combined suspension and emulsion of the protein or fragment thereof and the fat soluble vitamin.
With regard to the above two embodiments, the at least one fat soluble vitamin is vitamin E and said mammalian milk protein is a casein protein or a fragment thereof.
For this and other aspects of this invention involving non-milk compositions including at least one milk protein or protein fragment and vitamin E, the vitamin E is preferably at a level to provide at least 30 IU of alpha-tocopheryl acetate per unit dose or unit portion. Alternatively, the U.S. FDA recommended daily value (DV) for this vitamin is selected as an appropriate minimum dose. Whatever the DV happens to be at the present time (currently 30 IU), or at a future time, is considered appropriate as the minimum unit dose. Preferably, the unit dose is greater than 30 IU, and is between 50 and 100 IU of vitamin E per dose. In addition, in preferred embodiments, the composition of this aspect and other non-milk compositions including at least one milk protein or protein fragment, the composition is formed or packaged in unit dose or unit portion form. By xe2x80x9cunit dosexe2x80x9d or xe2x80x9cunit portionxe2x80x9d is meant that the composition is formed into pills, capsules, or other unit form providing a specific desired amount of the vitamin, micronutrient, or pharmaceutical agent per unit for ingestion by an individual mammal (preferably a human). Alternatively, or in addition, the composition is packaged in a form such as a foil or paper pouch or envelope to provide the specific desired amount of vitamin, micronutrient, or pharmaceutical agent. For example, the composition may be packaged in an individual use foil pouch in powder, granular, or pill form for combining with a liquid for consumption or for direct consumption.
In another aspect, this invention features a composition for oral administration to a human or other mammal, that includes a microdispersed mixture of at least one mammalian milk protein or fragment thereof, and at least one fat-soluble micronutrient or pharmaceutical agent, in which the weight ratio of said mammalian milk protein to said fat-soluble micronutrient or pharmaceutical agent is from 1:1 to 1000:1. In preferred embodiments, the ratio is in a sub-range as described for an aspect above. Preferably the composition is a non-milk composition as described above
In a preferred embodiment, the composition includes a microdispersed mixture of at least one mammalian milk protein or fragment thereof, and at least one fat-soluble pharmaceutical agent or micronutrient which is selected from the group consisting of fat-soluble analgesics, psychopharmacologic drugs, neurologic drugs, respiratory drugs, cardiovascular and renal drugs, hematologic agents, hormones and hormone effector drugs, gastrointestinal agents, anti-inflammatory agents, anti-allergic agents, immunologic agents, oncolytic agents, anti-infective agents, anti-poisoning drugs, metabolic agents, vitamins, and antioxidants. With the exception of vitamins and antioxidants, these terms are defined, and examples therein are provided in xe2x80x9cDrug Evaluations- 6th edition (1986), American Medical Association, Chicago, Ill. As discussed above, the fat-soluble vitamins include vitamins A,D,E and K. Fat-soluble antioxidants (other than the antioxidant vitamins) are also well known in the art, and include the tocotrienols, carotenoids, and alpha-lipoic acid (thioctic acid, CAS#62-46-4). Lipoic acid is a metabolic coenzyme that is also an antioxidant, and both fat- and water-soluble. The carotenoids are any of several highly unsaturated pigments such as the carotenes and xanthopyylls, most of which are yellow, orange or red, many of which occur in green plants and animals, and chemically characterized by a long aliphatic polyene chain compose of isoprene units.
Accordingly, in a preferred embodiment of the above, the composition includes at least one fat-soluble micronutrient or pharmaceutical agent selected from the group of fat-soluble antioxidants consisting of alpha, beta, gamma and delta tocopherols, alpha, beta, gamma and delta tocotrienols, the carotenoids, alpha-lipoic acid and combinations thereof. The structures of these chemical species are well known in the art. In yet another aspect, the invention features a method of forming a microdispersed mixture including the step of homogenizing an aqueous liquid mixture including at least one mammalian milk protein or fragment thereof, and at least one, i.e., one or more, fat-soluble vitamins, to thereby form a microdispersed aqueous liquid mixture. Preferably the one or more vitamins includes one or more of vitamins A, D, E and K.
In a preferred embodiment, the above method further includes the step of drying the above microdispersed aqueous liquid mixture, preferably by spray-drying or freeze-drying.
In another aspect, this invention includes a method for increasing the bioavailability of an orally administered fat-soluble micronutrient or pharmaceutical agent. The method consists essentially of: (i) providing a microdispersed mixture of at least one fat-soluble micronutrient or pharmaceutical agent, and at least one mammalian milk protein or fragment thereof, in which the weight ratio of the at least one mammalian milk protein or fragment thereof, to the at least one fat-soluble micronutrient or pharmaceutical agent is from 1:1 to 1000:1, or in a sub-range described above, and (ii) ingesting this microdispersed mixture.
In a preferred embodiment of the above method, the fat-soluble micronutrient or pharmaceutical agent is a fat-soluble vitamin supplement.
In another preferred embodiment, the fat-soluble vitamin supplement is vitamin E.
In contrast to prior art products, dairy products described in the present invention provide at least 31 IU of vitamin E per serving, preferably at least 40 IU per serving, and more preferably provide at least 50 IU per serving, allowing convenient consumption of at least 100 IU per day. This daily consumption of vitamin E is significantly greater than the Food and Drug Administration""s current recommended daily allowance (RDA) of 30 IU of the vitamin (1.0 IU=1.0 mg all-rac-xcex1-tocopherol acetate). Remarkably, the 92% average increase in the ratio of vitamin E/cholesterol in the bloodstream as a result of ingesting 100 IU microdispersed in milk each day significantly exceeds the rise resulting from ingesting even 200 IU of vitamin E in capsules each day, and approximates that rise expected from ingesting 300 IU per day in capsules (see FIG. 1 and Princen et al., 1995 Arterioscler. Thromb. Vasc. Biol., 15:325-333) Princen et al. showed that 200 IU vitamin E (all-rac-xcex1-tocopherol acetate) capsules increased the plasma vitamin E/cholesterol ratio 65%.
Despite the clinical knowledge that ingesting vitamin E in soft gel capsules at levels substantially in excess of 30 IU per day provides very significant health benefits with no undesirable side-effects, Applicants have been unable to find any food products containing vitamin E in excess of 30 IU per serving for delivery of vitamin E supplements. This can be explained by the recognition of those skilled in the art of the losses of vitamin E associated with the processing and storage of the food products, discouraging the introduction of any higher level of vitamin E into commercial foods, along with the lack of knowledge that milk provides a highly efficient delivery medium. That is, prior to the present discovery, there had been no finding, report or other evidence indicating that adding, dispersing or otherwise combining vitamin E with any food or beverage such could increase its bioavailability over other delivery modes.
To the contrary, results of experiments testing the bioavailability of a vitamin E dose in margarine or in a breakfast cereal were shown to be very similar to that of a simple supplement, e.g., in a capsule. Then, discouraging adding higher levels of vitamin E to foods (as more fully explained below), mixing, heat processing, e.g., pasteurization, and storing vitamin E in a food inevitably leads to significant losses (typically 25-35%) in its potency, i.e., the vitamin E is degraded. Indeed, it is generally recognized that tocopherols are usually added to food as antioxidants precisely due to their lability to oxidation, such that the tocopherol serves as a sacrificial compound to protect other compounds from oxidation (e.g., to retard the development of rancidity in oils). Therefore, it is generally understood that to obtain the maximum health benefit from larger doses of vitamin E, particularly from costly amounts of the vitamin, e.g., levels in excess of 30 IU per serving, the vitamin should be provided, stored and consumed in a more stable carrier or vehicle, such as in a gel capsule or tablet. With such a carrier, in the absence of any substances which may cause oxidative degradation, the activity of vitamin E can be maintained for many months. It is only with knowledge of hyper-absorption of vitamin E from milk, as disclosed in the present invention, that a reason or justification is created to add higher levels of vitamin E to milk products.
Accordingly, in a first aspect this invention provides a method for providing a composition suitable for reducing the daily ingested dose of vitamin E required for achieving at least a 50% increase in the plasma vitamin E/cholesterol ratio over the basal fasting plasma vitamin E/cholesterol ratio measured in the plasma of human subjects previously consuming no vitamin E dietary supplements. The method involves microdispersing vitamin E in a milk product, preferably a liquid milk product at a concentration sufficient to provide between 50 and 400 IU of vitamin E per serving of the milk product, measured after normal processing of the milk product, and preferably after storage under normal conditions for the normal shelf life for the product. The method also involves processing and packaging the product to provide a consumer-ready milk product having an adequate shelf-life. The reduction in the amount of vitamin E required is determined by comparison of the amount of vitamin E required to achieve the increase when ingested in the milk product with the amount of vitamin E required to achieve the same increase when ingested in a pharmaceutical preparation. The beneficial savings or reduction in the amount of vitamin E required for achieving the at least 50% increase, is at least 1.5-fold greater than the loss of vitamin E incurred during processing of the milk product. The pharmaceutical preparation refers to preparations of vitamin E in forms such as pills and capsules, e.g., a soft gel capsule. Preferably the milk product contains from 50 to 300, and most preferably from 50 to 200 IU per serving of the milk product after normal processing of the milk product. The method further involves processing and packaging the milk product to provide a consumer-ready milk product having an adequate shelf-life. The reduction in the amount of vitamin E required to provide the at least 50% increase over the basal plasma vitamin E/cholesterol ratio is greater, and preferably substantially greater than the loss involved in processing, preferably the reduction is at least 1.25 times the processing loss, more preferably at least 1.5 times, still more preferably at least 1.75 times, and most preferably at least 2.0 times the processing loss. Preferably the processing loss includes the storage loss during storage of the milk product under normal storage conditions for a normal shelf life period.
Likewise, the invention provides a method for reducing the amount of ingested vitamin E required to provide the specified increase in the plasma vitamin E/cholesterol ratio over the basal plasma vitamin E/cholesterol ratio by ingesting daily an amount of the milk product described above, sufficient to provide at least 50 IU of vitamin E. The ingestion of at least that amount is preferably continued for at least 200 days, and more preferably more than 200 days.
Furthermore, the invention provides compositions and methods for reducing the amount of ingested vitamin E required to provide a certain health benefit level, while substantially eliminating certain components of milk that are not required for vitamin E absorption. These components include milkfat, cholesterol and lactose that are found to be undesirable or poorly tolerated by some people. Accordingly, the protein component(s) of milk (and/or protein fragments derived from the digestion of this milk protein) can be used in the absence or substantial absence of the fat, cholesterol and carbohydrate components of milk to promote the enhanced uptake, i.e., gastrointestinal absorption, of vitamin E and other fat soluble vitamins, and other fat-soluble micronutrients and pharmacological agents. It is believed that the milk protein(s), including the most abundant protein component, casein (and fragments thereof), act to promote micelle formation which appears to be involved in gastrointestinal absorption.
In other embodiments, the milk product is as described for embodiments of aspects below which comply with the specification of this aspect.
In preferred embodiments of this and the other aspects of this invention, the milk product is preferably a fluid milk product.
In connection with the specification of levels of vitamin E in a milk product, the phrases xe2x80x9cfrom 50 to 200xe2x80x9d and xe2x80x9cbetween 50 and 200xe2x80x9d have the same meaning, referring to all levels from and including 50 up to and including 200. The same interpretation applies to any other numerical limits for ranges specified herein.
In another aspect, the invention provides a food-based vitamin E delivery system for achieving and sustaining a doubling of the basal fasting vitamin E/cholesterol ratio measured in the plasma of human subjects previously consuming no vitamin E dietary supplements. The food-based system includes a milk product fortified with from 50 to 400, preferably from 50 to 200, IU per serving of microdispersed vitamin E, providing a bioavailability-enhanced and cost-effective amount of supplemental vitamin E, where daily ingestion of an amount of the milk product sufficient to provide a dose of 100 IU achieves and sustains the doubling of the ratio. Preferably the daily dose of supplemental vitamin E microdispersed in the milk product required to achieve and sustain the doubling is ⅓ to xc2xd of the amount which would be required to achieve and sustain the doubling when ingested daily in the form of a capsule or pill. Preferably the milk product is a fluid milk product; preferably the milk product is substantially free of viable microorganisms. In preferred embodiments, the milk product is as described in aspects below which also fulfill the specifications of this aspect.
The term xe2x80x9cbioavailability-enhancedxe2x80x9d refers to an enhancement of bioavailability of vitamin E as compared to the bioavailability of the same form of vitamin E from a pharmaceutical preparation, e.g., from a soft gel capsule. The enhanced bioavailability allows the use of a reduced amount of vitamin E to produce the same enhancement of plasma vitamin E/cholesterol ratio as compared to delivery of the vitamin E is such a pharmaceutical preparation.
The term xe2x80x9ccost-effectivexe2x80x9d refers to the relative cost of providing vitamin E supplementation in milk as compared to current formulations of capsule forms, e.g., soft gel capsules, on the basis of equivalent bioavailability or basal fasting vitamin E/cholesterol ratio increases. Thus, a cost-effective milk product or vitamin E deliver system allows a smaller amount of vitamin E to be utilized, including processing and storage losses for normal shelf-life time periods.
Likewise, in a related aspect, the invention provides a cost-effective method for doubling the basal fasting vitamin E/cholesterol ratio in the plasma of human subjects previously consuming no vitamin E dietary supplements by providing a milk product as in the preceding aspect, and ingesting and continuing to ingest daily an amount of the milk product sufficient to provide at least 90 IU of vitamin E, and preferably at least 100 IU. Preferably the doubling of the basal fasting vitamin E/cholesterol ratio causes a decrease in the rate of LDL cholesterol oxidation in the bloodstream. Such a reduction in oxidation reduces the concomitant risk of atherosclerosis and coronary heart disease.
Also similarly, the invention provides a method for improving the economy of utilizing supplemental vitamin E in the human diet by providing and ingesting daily a sufficient amount of a milk product containing 50 to 400, preferably from 50 to 200 IU per serving of microdispersed vitamin E to provide at least 50 IU daily, rather than ingesting 2-3 times the amount in capsule form. In preferred embodiments, the milk product provides a 2-3-fold increase in bioavailability over the capsule form of vitamin E such that the increase in bioavailability outweighs the losses in vitamin E activity during processing and storage of the milk product. That is the reduction in the amount of vitamin E need to achieve a particular increase in vitamin E/cholesterol ratio is greater than the processing loss (as either amount or percentage). Preferably the ratio of beneficial reduction to undesirable loss is at least 1.25, 1.5, or 1.75.
In a related aspect, the invention features a milk product which includes at least 40 IU, and more preferably at least 50 IU of vitamin E per serving of the product and in other preferred embodiments at least 60, 80, 100, or even more IU of vitamin E per serving (e.g., 200, 300, 400 or 600). The product can conveniently provide at least 100 IU of vitamin E per day to an individual ingesting between ⅓and two servings of the product (e.g., xc2xd, 1, 2, 3, or 4 depending on the actual concentration of vitamin E in the product) though additional product can also be ingested to provide additional vitamin E. The vitamin E is uniformly microdispersed throughout the product. Ingestion of at least 100 IU of vitamin E per day in the product is sufficient to cause the fasting plasma vitamin E/cholesterol ratio in human subjects to be elevated at least 50% (and typically 80-90%) above the basal fasting vitamin E/cholesterol ratio measured in the same subjects consuming no vitamin E dietary supplements. Generally the elevation in vitamin E/cholesterol ratio approaches a plateau after approximately two weeks of daily ingestion of vitamin E fortified milk. Between two and four weeks, the ratio may still increase, but the proportion of increase is small (typically 5-20%) relative to the increase already achieved by two weeks.
In preferred embodiments of this and other aspects of this invention, the milk product is selected from the group of products including whole milk, reduced-fat milk, low-fat milk, skim milk, vegetable oil-filled milk, blended vegetable oil and milkfat-filled milk, lactose-reduced milk (milk in which some or all of the disaccharide milk sugar, lactose, has been enzymatically converted to the monosaccharides, glucose and galactose), butter milk, flavored milk, dairy-containing beverages, yoghurt, cream, sour cream, ice cream, cream cheese, cottage cheese, hard and soft cheeses (e.g., cheddar, Swiss and mozzarella), processed cheese (e.g., American cheese) butter and butter-containing spreads, puddings, eggnog, powdered and reconstituted milk, concentrated milk, condensed milk, milk-based infant formula, and the like.
In preferred embodiments, ingestion of at least 100 IU of vitamin E in the product (e.g., ingestion of 1 to 2 servings) is sufficient to cause the fasting plasma vitamin E/cholesterol ratio to be elevated at least 60% above the basal fasting vitamin E/cholesterol ratio measured in the same subjects consuming no vitamin E dietary supplements. In related embodiment, ingestion of at least 100 IU of vitamin E in the product (e.g., ingestion of 1, 2, 3, or 4 servings) is sufficient to cause the fasting plasma vitamin E/cholesterol ratio to be elevated at least 70%, 80%, or 90% above the basal fasting vitamin E/cholesterol ratio measured in the same subjects consuming no vitamin E dietary supplements.
In preferred embodiments, the milk product includes from 50 to 200, or from 100 IU to 400 IU of vitamin E per serving or from 70 to 200 IU of vitamin E per serving.
In preferred embodiments, ingestion of 100 IU of vitamin E per day in the product (e.g., ingestion of 1 to 2 servings) is sufficient to cause the fasting plasma vitamin E/cholesterol ratio to be elevated above the basal fasting ratio, to at least that ratio measured for subjects ingesting 200, and more typically 300, IU of vitamin E each day in the form of a pharmaceutical (pharmacological) supplement (e.g., a capsule containing vitamin E). The pharmaceutical supplement is orally ingested each day as either a single or a divided dosage, and is selected from the group consisting of capsules, pills, powders, and liquid preparations of vitamin E (not dispersed in a food product as vitamin E fortification).
In another preferred embodiment, ingestion of 100 IU of vitamin E per day in the product (e.g., ingestion of 1 to 2 servings) is sufficient to cause the fasting plasma level of vitamin E to be elevated between 700 and 1000 micrograms per deciliter (16-23 xcexcmol per liter) above the basal fasting level measured in the same subjects ingesting no vitamin E supplement. In related embodiments, the elevated plasma level of vitamin E is between 1700 and 2000 micrograms per deciliter.
In preferred embodiments the chemical form of the vitamin E in the milk product is selected from the group consisting of all-rac-xcex1-tocopherol acetate, all-rac-xcex1-tocopherol, RRR-xcex1-tocopherol acetate, RRR-xcex1-tocopherol and combinations thereof. The physical form of the vitamin E in the milk product is selected from the group consisting of water-dispersible and oil-dispersible preparations.
In preferred embodiments, the portion of the product throughout which the vitamin E is uniformly microdispersed, is selected from the group consisting of the fat portion, the fat-free milk portion, and combinations thereof.
In preferred embodiments, the milk product includes a milkfat-containing cream portion and an oil-dispersible preparation of vitamin E which is microdispersed throughout the cream portion and throughout the product. Alternatively, the milk product is a filled milk product which includes a polyunsaturated, and/or monounsaturated vegetable oil-containing cream portion which may also_include milkfat, and an oil-dispersible preparation of vitamin E which is microdispersed throughout the cream portion and throughout the product. Alternatively, the milk product is fat-free, and includes a water-dispersible preparation of vitamin E which is microdispersed throughout the product.
In another embodiment, ingestion of at least 100 IU of vitamin E per day (e.g., 1 to 2 servings) in said product for at least 4 weeks causes the fasting plasma vitamin E/cholesterol ratio to be at least doubled over the basal fasting plasma vitamin E/cholesterol ratio measured in the same subjects consuming no vitamin E dietary supplements. For example, the basal plasma ratio is between 5 and 6 micromoles of vitamin E per millimole of cholesterol, and the elevated plasma ratio is at least between 9 and 10 micromoles of vitamin E per millimole of cholesterol.
As described above, microdispersal of at least 50 IU vitamin E per serving in a milk product advantageously provides at least 100 IU in 1 to 2 servings. Recognition in the present invention that milk is a particularly effective delivery vehicle for vitamin E suggests that a level of vitamin E elevated above 30 IU per serving of milk is helpful, as it allows a quantity of vitamin E sufficient to provide substantial health benefits to be provided in fewer servings of a milk product than with previous milk products. Thus, in a related aspect, the invention features a milk product which includes at least 31 IU of vitamin E per serving of the product and preferably at least 40 IU per serving (or 50, 60, 80, 100, 200, 400 IU per serving). The vitamin E is microdispersed throughout the milk product. Daily ingestion of at least 50 up to 400 IU daily of the milk product causes the fasting vitamin E/cholesterol ratio to be elevated over the basal fasting vitamin E/cholesterol ratio to at least a two-fold greater extent than that elevation achieved by daily ingestion of the same quantity and chemical species of vitamin E provided in the form of a pharmacological capsule or pill. By contrast, with lower levels of vitamin E ingestion, such as 30 IU per day, only small, if any, differences exist between the absorption from capsules compared to absorption from milk.
With reference to the basal fasting vitamin E/cholesterol ratio, the term xe2x80x9cdoublexe2x80x9d or xe2x80x9cdoublingxe2x80x9d means that the ratio has increased at least 80%.
In still another aspect, the invention features a method for elevating the fasting plasma vitamin E/cholesterol ratio at least 50% more preferably at least 60%, most preferably at least 80%, or more, in human subjects. The method includes the steps of providing a milk product with at least 50 IU of microdispersed vitamin E per serving, or preferably at least 60, 80, 100 or more (e.g., 200, 300, 400 or 600 IU per serving) (these levels are also applicable to aspects described below) of the product. The product can provide at least 100 IU of vitamin E per day to an individual ingesting between 1 and 2 servings of the product (depending on the actual vitamin E concentration in the milk product). At least 100 IU of vitamin E in the milk product is ingested daily for at least 2 weeks to cause the plasma vitamin E/cholesterol ratio to be elevated at least 50% preferably at least 60% and more preferably, at least 80% above the basal fasting vitamin E/cholesterol ratio measured in the same subjects consuming no vitamin E dietary supplements.
In yet another aspect, this invention features a method for reducing the incidence of non-fatal heart attacks by at least 50% in subjects having normal vitamin E uptake, and/or in subjects having coronary atherosclerosis. The method includes providing a milk product which includes at least 50 IU (preferably at least 60, 80, 100 or more IU) of vitamin E per serving of the product. The product provides at least 100 IU of vitamin E per day to an individual ingesting between 1 and 2 servings of the product (depending on the actual concentration). The vitamin E is uniformly microdispersed throughout the product. At least 100 IU of vitamin E in the product is ingested per day for at least 2 weeks to cause the fasting plasma vitamin E/cholesterol ratio to be elevated at least 50%, preferably at least 60%, 80% or more above the basal fasting vitamin E/cholesterol ratio measured in the same subjects consuming no vitamin E dietary supplements. This regimen is continued for at least 200 days and preferably indefinitely beyond. After these first 200 days, the reduced incidence of non-fatal heart attacks becomes apparent.
In reference to ingestion of a milk product, the phrase xe2x80x9cingested per dayxe2x80x9d, or similar indications of daily practice, means nearly every day during a period or interval, but also includes each and every day. This can, for example, include every day, missing one day in a month, missing one day in each 2 weeks, or missing one day in each week, or missing days irregularly which average intervals as indicated. For obtaining the health benefits, the blood or plasma level should be maintained at an elevated level of at least 80% of the days in an interval, preferably, at least 90%, more preferably at least 95%, and most preferably at least 98% or even 100% of the days. The elevated level is at least 50%, preferably 60%, more preferably 80% over the basal fasting level.
For any aspect of this invention which specifies daily ingestion, in related aspects, the requirement of daily ingestion is replaced with the limitation that the plasma vitamin E/cholesterol ratio is increased at least 60%, preferably at least 70%, more preferably at least 80%, and most preferably at least 90% over the basal fasting ratio for individuals not previously consuming any vitamin E supplements. Thus, in these aspects, the ingestion can deviate from strictly daily so long as the ingestion is sufficiently consistent to maintain the plasma vitamin E/cholesterol ratio elevation at the specified level. To some extent, such maintenance can be accomplished by ingestion of even higher levels of vitamin E, even though on a less than daily frequency.
In preferred embodiments of the various aspects of this invention, the milk product; vitamin E; levels of vitamin E in the milk product; and/or plasma levels of vitamin E are as described above, including, in particular embodiments described for the first aspect.
In still another aspect, the invention features a method for beneficially fortifying a milk product with a defined quantity and chemical form of vitamin E. The milk product includes at least 31 IU of microdispersed vitamin E, preferably at least 40 or 50 IU, more preferably at least 60, 80, 100, 200, 400, or more IU per serving of the product. Daily ingestion of an amount of the milk product containing at least 100 IU causes an increase in the fasting plasma vitamin E/cholesterol ratio which is at least two-fold greater than that increase caused by daily ingestion of the same defined quantity and chemical form of vitamin E provided in the form of a pharmacological capsule or pill in the forms currently prepared. The method includes microdispersing the defined quantity and chemical form of vitamin E throughout the milk product.
In preferred embodiments of methods for fortifying a milk product and other aspects described herein, the chemical form of the vitamin E in the milk product is selected from the group consisting of all-rac-xcex1-tocopherol acetate, all-rac-xcex1-tocopherol, RRR-xcex1-tocopherol acetate, and RRR-xcex1-tocopherol. The milk product is preferably selected from the group consisting of regular milkfat-containing milk; fat-free skim milk, polyunsaturated fat-containing filled milk, and combinations thereof. Preferably the fat components of the milk product together provide a balanced fat.
For the purposes of this invention, the following terms have the following meanings in context.
The term xe2x80x9cmilk productxe2x80x9d includes milk and/or cream-based products in whatever form, including, for example, liquid milks [including fat-free skim milk, whole milk, low-fat milk, reduced fat milk, butter milk, lactose-reduced milk and filled milks in which the milkfat portion of the milk is partially or completely replaced by a monounsaturated vegetable oil (e.g., canola oil) or a polyunsaturated vegetable oil (e.g., soybean oil)], as well as yoghurts, creams, sour cream, ice cream, cream cheese, cottage cheese, hard and soft cheeses, processed cheese, e.g., American cheese, buttermilk, eggnog, powdered and reconstituted milk, concentrated milk, condensed milk, and milk-based infant formula. The definitions of International Unit (IU) and its relationship to the xe2x80x9cquantityxe2x80x9d (mass, generally in milligrams) and xe2x80x9cchemical formxe2x80x9d (all-rac-synthetic versus RRR-natural forms of xcex1-tocopherol and xcex1-tocopherol acetate) are discussed above.
The term xe2x80x9cservingxe2x80x9d or xe2x80x9cserving sizexe2x80x9d is defined by the Food and Drug Administration (FDA) for most varieties of prepared foods. For milk, for example, a single serving equals 8 ounces (1 cup or approximately 236 ml).
The term xe2x80x9cmicrodispersedxe2x80x9d or xe2x80x9cmicrodispersingxe2x80x9d with regard to fat-soluble vitamin E (tocopherol or tocopherol acetate) refers to a process for blending or dissolving the vitamin E into the cream (milkfat-containing) portion of regular milk, or into the vegetable oil (e.g., soybean oil) component or blended vegetable oil and milkfat component of filled milks, and then pasteurizing and homogenizing the milk to reduce the diameter of most ( greater than 90%) of the fat particles to less than 2 microns. Thus, microdispersal ultimately distributes vitamin E into the small, stable microscopic fat particles which are present in homogenized milk. In the case of skim milk and other fat-free foods, the vitamin E is generally added as a pre-mixed, water-dispersible blend. For example, Roche Vitamins, Inc. (Paramus, N.J.) and Watson Foods Co., Inc (West Haven, Conn.) produce all-rac-xcex1-tocopherol acetate in cold water-dispersible powder forms containing approximately 50% by weight vitamin E and 50% by weight of an emulsifier/dispersant system. In the Roche product, the dispersant consists primarily of dextrin and gelatin in a 3:2 weight ratio, while in the Watson product (used in the present clinical study), the dispersant is modified food starch. These dispersant systems allow the vitamin E to remain stably suspended, in a fine colloidal dispersion, within skim milk. To assure microdispersal of vitamin E throughout skim milk, the milk was pasteurized and homogenized, using methods well known in the art, after the water-dispersible vitamin E had been added to the milk. It is unknown whether microdispersal of vitamin E in skim milk is aided by natural components of the skim milk including the milk proteins, casein and lactalbumin, for example. The term xe2x80x9cmicrodispersalxe2x80x9d with regard to vitamin E dispersal in a milk product, also has a functional definition. If the vitamin E has been sufficiently well mixed, blended, emulsified, homogenized, or otherwise dispersed into a milk product, it has been xe2x80x9cmicrodispersedxe2x80x9d if the bioavailability of a dose of vitamin E, when tested in humans is at least two times (e.g., 2-3 times) greater (i.e., the increase over basal fasting vitamin E/cholesterol ratio in the subject""s plasma is 2-3 times greater) than that measured using the same dose of vitamin E ingested in the form of a soft gel capsule. As evidenced in the research reported in Dimitrov et al., Am. J. Clin. Nutr. 53:723-729, 1991, merely ingesting oil-dispersible vitamin E together with milk, and obtaining natural mixing (and perhaps partial emulsification) in the stomach and small intestine, is not sufficient for achieving the improved bioavailability of the vitamin E.
The term xe2x80x9cfasting plasma level of vitamin Exe2x80x9d means that concentration of vitamin E measured in the plasma or serum fraction of the blood following an overnight fast by the subject of at least 10 hours.
The term xe2x80x9cbasal fasting level of vitamin Exe2x80x9d refers to that fasting plasma level of the vitamin measured in subjects who have ingested no vitamin E supplements and a normal diet (i.e., not unusually rich in vitamin E) for at least 4 weeks time. Similarly, reference to xe2x80x9cnot previously ingested vitamin E supplementsxe2x80x9d or a similar terms indicates that vitamin E supplements have not been consumed by the person for at least 4 weeks.
Similarly, the term xe2x80x9cfasting plasma vitamin E/cholesterol ratioxe2x80x9d refers to the blood plasma or serum concentration of vitamin E divided by the plasma total cholesterol concentration, measured in subjects following an overnight fast of at least 10 hours.
Also similarly, the term xe2x80x9cbasal fasting vitamin E/cholesterol ratioxe2x80x9d refers to the same basal fasting measurements in which the basal fasting plasma or serum vitamin E concentration is divided by the plasma total cholesterol concentration measured under the same dietary conditions. With the milk or dairy products of the present invention, ingestion as described generally causes an increase in the fasting plasma level of vitamin E. However, utilization of the plasma vitamin E/cholesterol ratio to measure the effect of ingesting the present dairy products is advantageous as the cholesterol level provides a normalizing factor, thereby simplifying data interpretation as there is less interindividual and intraindividual fluctuation in the ratio than in the plasma vitamin E level. Also, the ratio is believed to be more representative of the biologically significant role of vitamin E than is the absolute plasma vitamin E.
The term xe2x80x9cpharmaceutical supplementxe2x80x9d or xe2x80x9cpharmacological supplementxe2x80x9d in connection with delivery or ingestion of vitamin E refers to a composition prepared for human consumption primarily to deliver the vitamin E or vitamin E in combination with other vitamins, and which therefore contains the vitamin E in concentrated form. Thus, the term include, for example, pills and capsules. The term refers to such preparations as currently formulated or functional equivalents when used in connection with comparison of the relative bioavailability or absorption of vitamin E ingested in pharmaceutical supplement form as compared to a different delivery mode. This recognizes the possibility that at some time in the future, a pharmaceutical supplement, perhaps containing emulsifiers and/or a vitamin E-binding factor or carrier, might be developed which provides significantly better bioavailability than current preparations, e.g., current gel capsule forms. However, the term excludes general food products.
The term xe2x80x9cbalanced fatxe2x80x9d is defined hereinafter. Recent human clinical studies described in Sundram et al., U.S. Pat. No. 5,578,334 and Sundram et al., U.S. Pat. No. 5,843,497 have shown that an approximately equal balance of dietary polyunsaturated and saturated fatty acids (which can be provided by a combination of vegetable fats with or without animal fat such as milkfat) generally provides the best serum cholesterol profile in terms of reducing the LDL cholesterol level while sustaining or increasing HDL cholesterol to produce a favorable increase in the ratio of HDL to ILDL cholesterol. Accordingly, a xe2x80x9cbalanced fatxe2x80x9d is any fat, fat blend, chemically modified fat, and the like (of vegetable and/or animal origin), containing between 15% and 40% by weight polyunsaturated fatty acids and between 20% and 40% saturated fatty acids by weight. Preferably, the balanced fat contains less than 1% elaidic acid or other unnatural trans fatty acid.
The term xe2x80x9cabsorptionxe2x80x9d, and the extent of such absorption, such as xe2x80x9chyper-absorptionxe2x80x9d (higher than normal or unexpectedly efficient absorption) is used in the context of the level of vitamin E measured in either the plasma, lipoproteins, and/or in various cellular tissues. It is intended to include both the primary process of vitamin E transport into the bloodstream from the gastrointestinal tract, and to any secondary event(s) subsequent to the primary uptake process, e.g., liver-associated events, which may lead to an elevation in the measured levels of vitamin E. Thus, the term xe2x80x9cabsorptionxe2x80x9d is not limited to the primary absorption process of vitamin E uptake into the bloodstream following vitamin E ingestion. As a hypothetical example, if vitamin E were rendered more persistent or stable in the bloodstream by having been ingested in milk, the resulting increase in the plasma level of vitamin E would also be referred to as xe2x80x9cincreased absorption.xe2x80x9d
As used in the claims to describe the various inventive aspects and embodiments, xe2x80x9ccomprisingxe2x80x9d means including, but not limited to, whatever follows the word xe2x80x9ccomprisingxe2x80x9d. Thus, use of the term xe2x80x9ccomprisingxe2x80x9d indicates that the listed elements are required or mandatory, but that other elements are optional and may or may not be present. By xe2x80x9cconsisting ofxe2x80x9d is meant including, and limited to, whatever follows the phrase xe2x80x9cconsisting ofxe2x80x9d. Thus, the phrase xe2x80x9cconsisting ofxe2x80x9d indicates that the listed elements are required or mandatory, and that no other elements may be present. By xe2x80x9cconsisting essentially ofxe2x80x9d is meant including any elements listed after the phrase, and limited to other elements that do not interfere with or contribute to the activity or action specified in the disclosure for the listed elements. Thus, the phrase xe2x80x9cconsisting essentially ofxe2x80x9d indicates that the listed elements are required or mandatory, but that other elements are optional and may or may not be present depending upon whether or not they affect the activity or action of the listed elements.
Additional features and embodiments will be apparent from the following Detailed Description of the preferred embodiments and from the claims.